MCP SDK
Components for building MCP servers and clients that enhance LLM reasoning with custom data, code, and context.
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Connect LLMs to Your Applications
The Model Context Protocol (MCP) standardizes how large language models interact with external systems, making it possible to expose custom data, functionality, and predefined instructions in a way models can use programmatically. MCP gives you a structured way to connect LLMs to your organization's data, tools, and workflows, making their output more relevant to your specific needs.
MCP SDK is a development library that streamlines implementation of MCP servers and clients. Our components use an intuitive event-driven API that enables LLMs to retrieve relevant data, trigger custom operations, follow reusable instructions, and more. Whether you're building AI agents or integrating LLMs into backend systems, MCP SDK acts as the connective layer between language models and your application logic. MCP SDK supports all major protocol features like tools, sampling, prompts, and resources.
Bi-Directional Communication
MCP SDK enables seamless, two-way communication between your systems and LLMs. MCP servers built with MCP SDK can expose custom functionality, resources, and prompts that LLMs can call in real time. Clients built with MCP SDK act as the bridge between LLMs and those server-side capabilities by initiating requests and retrieving data, functionality, and instructions that reflect your organization’s unique context.
Easy Setup
MCP SDK ensures that interfacing with LLMs is as easy as possible. With just a few basic configuration settings, MCP hosts can launch your MCP server quietly in the background to facilitate communication. Whether you want to communicate over standard input and output or HTTP, MCP SDK minimizes the overhead required to integrate with all standard MCP hosts.
MCP Tool Support
Enable your LLM client to execute custom code by defining Tools available within query contexts.
Flexible Resource Integration
Provide your LLM with data through user-defined data Resources. Serve data from a file, database, cloud repository, and more.
Pre-Defined Prompts
Template common LLM prompts for reusability, with support for dynamic arguments and resource contexts.
Sample LLM Logic in Code
Bi-directional integration with your LLM client means you can query LLM reasoning within your Tools and custom code.
Uniform & Extensible Design
Very easy to use, with a uniform, intuitive, and extensible design. Common component interfaces across platforms and technologies.
Fully Integrated Components
Native software components for any supported development technology - with no dependencies on external libraries.
Red Carpet Vol. 2 2025 Now Available
New Tools for In-Browser Signatures, Cloud Spreadsheet Integration, SFTP Server Hosting, PDF Form Filling, and More
The latest release of our signature Red Carpet Subscription is now available, including three new products: PKI Agent for in-browser signing using system certificates, Cloud Sheets for integrating spreadsheet management into your apps, and CoreSSH Server for hosting simple and secure SFTP & SSH servers. In addition, this update brings Cloud Calendars and Cloud SSO from beta into full release, adds support for creating and filling PDF forms to Secure PDF, and much more.
Download MCP SDK or read the update highlights.
Product Features
MCP SDK includes an MCP Server component for building customized MCP servers that facilitate bi-directional communication with LLM clients.
- Full support for all major MCP features, including resources, prompts, sampling, and tools.
- Simplified handling of MCP server events through a simple, intuitive component API.
- Flexible server implementation allows for custom logic to determine what resources your LLM can access.
- Supports standard input and output channels as well as HTTP.
- Enable LLM access to your applications' unique data and logic.
- Make custom application logic callable by LLMs.
- Works seamlessly with existing MCP hosts like Claude Desktop, Cursor, VS Code, and more.
- A complete unified framework with a common, easy-to-learn object model and simplified interfaces that enable you to do more.
- Components are thread-safe on critical members.
- Fast, robust, reliable components that consume minimal resources.
- Native development components for all supported platforms and technologies.
- Rigorously tested, rock solid libraries that have undergone hundreds of thousands of hours of testing both internally by our QA team and externally through customer installations.
- Detailed reference documentation, sample applications, fully-indexed help files, and an extensive online knowledge base.
- Backed by multi-tier professional support, including free email support and enterprise-level paid support.
Supported Platforms
.NET
.NET Framework & Cross-platform Components
Based on a 100% C# codebase, with no dependencies on native code. The edition of choice for all .NET applications.
Cross-platform support for Windows, Linux, macOS, and anywhere .NET is supported. Due to OS limitations, not all features are available on all operating systems. Native libraries are also available for individual platforms.
- Fully-managed .NET components written in C#.
- Support for .NET 9, .NET 8, .NET 6, .NET 5, .NET Core 3.1, and earlier.
- Support for .NET Framework 2.0 - 4.8.
- Works with Xamarin and MAUI via .NET 6.
- .NET Standard 2.0 and 2.1 support.
- Fully asynchronous API available.
- Cross-platform support.
- Support for Windows IoT.
- Comprehensive integrated product documentation.
- Seamless integration with Visual Studio.
- Extensive sample applications written in C#.
Java
Pure Java Classes (Java/J2EE)
Pure Java Classes exposed through an intuitive API for portability across all major platforms.
- Pure Java Classes.
- Includes an extensive library of samples written in pure Java.
- J2EE version is optimized for server-side development.
- Seamless integration with popular development environments including JBuilder, Eclipse, and IntelliJ.
- Support for JDK version 1.7 and up.
Included Samples
The following sample projects are installed with the product. Please download the trial to get started.
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